“The Land of the Great Horses” by R.A. Lafferty

“Are the two of us as crazy as the country?'” Rockwell moaned. “I’ve worked with you for three years. Isn’t your name Smith?”

“Why, yes, sir, I guess it might be Englished as Horse-Smith or Black-Smith. But my name is Pettalangro and I’m going home.”

You’ll find “The Land of the Great Horses” in the anthology Dangerous Visions: FIC DANGEROUS

Smith and Rockwell are scientists lost in a desert in India. Both experience an unexpected thunderstorm. Both watch the landscape change from desert to plain. Rockwell is convinced it’s a mirage while Smith seems to think it’s all perfectly natural. In fact, Smith is starting to feel quite at ease.

I don’t want to give too much away. This story baffles until the last page or so and I think it’s best read that way. Harlan Ellison, who included it in the classic anthology Dangerous Visions, called it “one of my particular favorites,” and I think you’ll agree.